Food chains and webs

In an ecosystem, plants and animals all rely on each other to live. Scientists sometimes describe this dependence using a food chain or a food web. Read on to find out more information and play some fun games!

Food chain

All living things need food to give them the energy to grow and move. A food chain shows how each living thing gets its food. It shows who is eating who. The arrow is read “is eaten by”.There are names to help describe each link of the food chain. The names depend mostly on what the organism eats and how it contributes to the energy of the ecosystem.

Here is an example of two food chains:

Producers:

Plants are producers. This is because they produce energy for the ecosystem. They do this because they absorb energy from sunlight through photosynthesis. They also need water and nutrients from the soil, but plants are the only place where new energy is made.

Consumers:

Animals are consumers. This is because they don’t produce energy, they just use it up. Animals that eat plants are called primary consumers or herbivores. Animals that eat other animals are called secondary consumers or carnivores. If a carnivore eats another carnivore, it is called a tertiary consumer. Some animals play both roles, eating both plants and animals. They are called omnivores. Humans are examples of omnivores.

Decomposers :

Decomposers eat decaying matter (like dead plants and animals). They help put nutrients back into the soil for plants to eat. Examples of decomposers are worms, bacteria, and fungi.

Energy:

Like we said above, all the energy made in the food chain comes from the producers, or plants, converting sunlight into energy with photosynthesis. The rest of the food chain just uses energy. So as you move through the food chain there is less and less energy available. For this reason, there are fewer organisms the closer you get to the end of the food chain.

For example, there is more grass than zebras, and more zebras than lions. The zebras and lions use up energy doing things like running, hunting, and breathing.

Food Web

In any ecosystem there are many food chains and, generally, most plants and animals are part of several chains. When you draw all the chains together you end up with a food web.